No. 1 Alabama is understandably big favorites when it hosts SEC rival Arkansas on Saturday. That doesn't mean this game is a lock for the two-time defending national champions.

While the Crimson Tide clearly outclass the Razorbacks in overall talent and have already faced far more complete tests this season, Arkansas will test the Crimson Tide defense in a way it hasn't been this year.

That is because the Razorbacks feature a physical and effective ground game in a conference that has gone almost exclusively to the spread attack.

Arkansas enters this game having lost four straight and it's getting worse by the week. However, if they can get the ground game on track early, control possession and gain some confidence, an upset of poll-shaking proportions is not out of the question.

The Razorbacks are 24th in the nation in rushing yards, and they feature two backs in the top six in the SEC in rushing.

The monster two-headed rushing attack of Arkansas begins with running back Alex Collins. The freshman has been outstanding while gaining 720 yards at 5.9 yards per carry.

He's been a workhorse this season. Lately, the only thing that has slowed him down has been Arkansas' inability to keep games close. The Razorbacks have been outscored by a combined 52-17 in their last two games.

As a result, Collins is coming off the most anemic two-game stretch of his young college career with just 123 combined rushing yards over that stretch. However, that's come on just 23 total carries, so it's not like he's being stonewalled at the line of scrimmage.

Now he will face an Alabama defense that is getting stronger as the season rolls along. The Crimson Tide have allowed just 206 rushing yards over the last four games.

However, all four of those games have been blowouts, the closest was a 25-0 win over Ole Miss, and that doesn't give us a great indication of the whole picture of the rush defense.

In Nick Saban's 3-4 defense, his defensive linemen are huge. While this serves them well in eating up blockers in the run game, it also leaves them vulnerable to fatigue. If Arkansas controls the ball enough, it can wear that front down.

And Arkansas can keep punishing defenses with their talented backs.

Not only do the Razorbacks have Collins to hand off to, but Jonathan Williams brings another dynamic option in the backfield. At 6' and 220 pounds, the sophomore is a load to bring down, and he's also enjoying a nice season. He's gone for 564 yards gained at an average of 6.5 yards per carry.

Like Collins, his numbers have dipped the last two weeks, but he's still running well when getting his limited opportunities.

Two weeks ago, the Razorbacks faced Florida's mighty defense. The Gators lead the SEC in rush defense, one spot ahead of the Crimson Tide. Still, Collins and Williams both averaged at least four yards per carry.

Of course, with the passing game hitting just 17 of 43 passes, the offense was still limited to just 10 points.

With a limited passing game, Arkansas own the nation's 113th-ranked passing attack, it is difficult to see the Razorbacks sustaining drives. However, if they can consistently churn out positive yards with a heavy dose of the run game, they will have some easy looks off of play action and will be able to keep the aggressive Alabama defense off guard.

This is a tall order, but it is the Razorbacks only path to a victory.